
body footer {
  position: fixed;
  display: flex;
  justify-content: space-between;
  bottom: 0;
  box-sizing: border-box;
// 继承body的宽度
  width: inherit;
  padding-top: 5px;
  padding-bottom: 5px;
  background: rgba(255, 255, 255, 0.8);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
}

footer span {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: space-around;
  align-items: center;
  text-align: center;
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
}

footer span i {
  width: 14px;
  height: 14px;
  display: block;
  margin: auto;
  margin-bottom: 2px;
  vertical-align: middle;
}

footer span i.homeIcon {
  background: url(../icons/homeIcon.svg);
}
footer span i.searchIcon {
  background: url(../icons/searchIcon.svg);
}
footer span i.bookIcon {
  background: url(../icons/bookIcon.svg);
}
footer span i.aboutIcon {
  background: url(../icons/aboutIcon.svg);
}

footer span a {
  font-size:12px;
  color: #111;
}